I remember watching episodes of several Gundam titles on and off back when Toonami
was still airing on Cartoon Network yet the one that I did watch a majority of was G Gundam. Back then, I was glued on seeing what I could of the series while I was in high school thanks to the sight of seeing giant robots fight one another in a world tournament. But after having seen the show years later, the show hasn't really aged too well for me. Pretty much, the entire show has the feel of a shounen
action anime where the plot is mostly a backdrop for mecha fights piloted by martial artists who regularly train for the sake of getting stronger and getting deep into self-doubt when up against a stronger foe where without anyone around to knock sense into them, said character would be too dense to know what to do, thus Plot Induced Stupidity
sets in. Characters brag about their "super special ultra secret" techniques, evil characters have the annoying habit to laugh evilly at their deeds and have little depth, the series has enough of a habit overemphasizing the importance of fights and all the other standard formulas of shounen. The major problem with sticking to these formulas is that potential areas of plot exploration such as the development of Rain and Domon's bond and the tensions between Master Asia and Domon are put to the back-burner just to show off the fights and when the show finally decides to focus on them, the handling of the plots didn't hook me in thanks to the heavy focus on fights. On the visual end, G Gundam is tolerable at points (good looking mecha designs and decent scenery) yet just awful in others (animation's poor, a number of reused animation frames, character designs are often off).
There are a couple positives that did keep me somewhat interested. A few of the side characters in the show did well at contributing some comedy such as the monks that accompany Sai Saici and George De Sand's butler. I even got some laughs at the expense of some silly looking mecha designs such as a couple Gundams shaped like a windmill and a bull. An episode focused on Sai Saici having his first romantic interest was the best episode I seen of the show where it did devote enough focus on the interactions between Sai and his interest.
Beyond that, G Gundam is a mecha anime following your cookie-cutter shounen anime tropes which while not all-out horrible, isn't too original and with much of the show's focus on mecha fights, those wanting more fleshing out with their anime won't be enjoying this series too well.